Thread-protector for tubing



(No ModeL) 2 Shets-8heet 1.

J. W. ABRAHAMS.- THREAD PROTECTOR FOR TUBING No. 556,127 Patented Mar. 10; 1896.

(No Model.) I 2 SheetsSheet 2.

. J. W. ABRAHAMS.

THREAD PROTEGTOR FOR TUBING.

No. 556,127. Patented Mar. 10, 189.6.

UNITED STATES PATENT OFFICE.

JOHN NVM. 'ABRAHAMS, OF ALLEGHENY, PENNSYLVANIA.

THREAD-PROTECTOR FOR TUBING.

SPECIFICATION formingpart of Letters Patent No. 556,127, dated March 10, 1896.

I Application filed August 8, 1895. Serial No. 558,676. (No model.)

To all whom it may concern:

Be it known that I, JOHN WM. ABRAHAMS, a resident of Allegheny, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Thread-Protectors for Tubing; and I do hereby declare the following to be a full, clear, and exact description thereof.

My invention relates to pipe-thread protectors and the manufacture of the same. These protectors are screwed onto the threaded ends of wrought-metal pipes to protect the thread from injury by blows in the shipment of the pipes, and when the pipes reach their destination and are put in use the pipethread protectors are generally screwed off and thrown away. As the pipes are often subjected to very heavy blows it is necessary for the protectors to be made strong to shield them from the blows, and further to prevent the bending of the ends of the pipes out of their true circular form, while, as the protectors are generally used but once, it is necessary that they shall be made cheap, so as to add but little to the cost of the pipe; and the object of the present invention is to provide such a protector at small cost and one which will efficiently serve the purpose.

To these ends my invention consists, generally stated, in a thread-protector formed of two or more spirally-wound coils of metal strip with thread impressions formed on the inner face thereof, said strip having one of its ends bent inwardly and overlapped by the coil.

It also consists in an apparatus for forming the pipe-thread protectors, comprising, generally stated, a rotating threaded mandrel and a rotating guiding-roll adapted to feed a strip thereto and longitudinally yielding as the strip is wound upon the mandrel, and in the employment of holding means to engage the end of the strip and flanges between which the coils of the strip are compressed, so as to bring the same to the desired shape.

It also consists in certain other improvements which will be hereinafter more particularly set forth and claimed.

To enable others skilled in the art to employ my invention I will describe the same more fully, referring to the accompanying drawings, in which Figure 1 is a perspective View of a pipethread protector embodying my invention. Fig. 2 is a View of another form of the same. Fig. 3 is a view of the preferred form of strip employed for forming the protector. Fig. 4 is a view of the protector at the end of a pipe. Fig. 5 is a side view of the machine employed for forming the protector. Fig. 6 is an enlarged side view of the upper part of said machine, illustrating the operation of forming the same. Fig. 7 is a like view showing the method of removing the protector, and Fig. 8 is a sectional View in side elevation on the line 8 8, Fig. 5.

Like letters of reference indicate like parts in each.

In forming the pipe-thread protectors embodied in my invention I employ a wroughtiron or steel metal strip of desired section. For example, as shown in Figs. 1 and 3, it may be a strip of sufficient width to form the protector or a couple of coils thereof, the strip therefore being of greater width and thickness, and its width and thickness varying according to the size of pipe for which the protector is formed and the extent of the threaded end thereof which is to be covered by the protector and the thickness of the metal necessary in the protector to prevent injury to the pipe. The protector may also be formed of strips of practically the same width and thickness, as shown in Fig. 2, in

which case a larger number of coils is of course required.

In the protector shown in Fig. 1 it Will be seen that the body portion is formed of two spirals CL, and that the end portions of the strip. forming the spirals are tapered down, as at b, so as to make the protector of practically the same length throughout, this being ac complished by the strip substantially such as shown in Fig. 3, and, as illustrated by said figure, the necessary shapes of the strips being obtained by cutting diagonally through the strips, as at c, to form the tapered ends I) on the strip from which the coiled protector is formed. For the purpose more fully hereinafter set forth I prefer to turn one of the ends of the strip inwardly, as at a. On the inner face of this coiled tubular body so obtained are formed the threads or thread-impressions cl, which conform to the threads of ICO the pipe and may correspond in depth thereto, or, as preferred by me for eheapness, may be of but slight depth, so as to engage with the upper edges only of the threads of the pipe, this being desirable because in such case it may be formed in the way hereinafter described without the actual tapping to the tubular thread-protector.

In the thread-protector of Fig. 2 it is not necessary to form tapered portions on the strip because of the small width of the strip from which is coiled the form of the protector, and consequently it may be formed by a mere straight bar or strip of proper section. It will be noticed that the protector is coiled in the same direction as the thread is formedthat is, for the ordinary right-hand-thrcaded pipe the protector is coiled in the same direction. This is very desirable in such protector, because in screwing the same onto the pipe it will naturally spring open slightly, being screwed on in a direction which would tend to open the spirally-coiled protector, and consequently it can be screwed on by hand with but little force. lVhen, however, the protector is to be withdrawn from the pipe, as the natural movement of it is in the opposite direction-that is, in the direction opposite to the coil of the proteetor-tl1e tendency is to cause the protector to bind around the pipe, and therefore it requires considerably more force to unscrew it and will generally require a wrench for that purpose. For like reason any blows or rough handling that might lead to the unscrewing of the protector will. be overcome by this natural tendency of the protector to bind upon the pipe when it is unscrewed.

These pipe-thread protectors can be formed in any desired way, but I prefer to form them in the way herein described, for the reason that they can be produced rapidly and at low cost, and therefore, while possessing the peculiar advantages above described, they can be placed upon the market at but little above the cost of the metal. in coiling the metal strip around a threaded mandrel in such way as to impress the thread of the mandrel into the inner face sulficiently to enable the protector to hold to the threads of the pipe. The machine illustrated in the drawings provides an easy and simple way of practicing this method, and I will now describe it.

The machine-frame f is preferably formed of a single casting and has suitable bearings for supporting the shaft -for example, the bearings f f for supporting the main shaft g, which carries at its forward end the threaded mandrel h, around which the strip is to be coiled in forming the pipe-thread protector. Said shaft 9 also carries suitable reversing mechanism and such as to band the wheels g g 9 and carrying the pinion 9 Below this shaft g is the shaft z' carrying the pinion 'i,1n eshin g with the pinion 9 so that said shaft is turned in the opposite direction. This This method consists shaft is mounted in the bearing 1?, which is pivoted to the machineframe at i so as to swing in the direction of the length of the shaft, and the opposite end of the shaft is mounted in the yoke 75, which has the bearings 7a 7.2 thereon, and which provides for vertical movement of this end of the shaft. This vertical movement is obtained by the vertical shaftl passing through the guideway Z, in the upper end of which is the hinge or pivot 76 in which the yoke 7c is mounted, while the lower end is connected to the foottreadle Z which is mounted in the bearing 1, provision thus being made so that when the foot is placed upon said treadle the vertical shaft 5 is raised and with it raises the yoke 7.: and the outer or free end of the shaft 2', and when the foot is withdrawn the free end of said shaft 2' is permitted to drop a short distance, the pivot-bearing 76 at the upper end of the shaft 1 having a shoulder k resting on the sleeve Z and limiting the downward movement of the parts operating the free or outer end of the shaft 2'. This shaft 2' carries the roll m, which has a sliding connection therewith, such as an ordinary slot-and-key connection, and which serves to hold the metal strip up to the mandrel 7L. It will be noticed that the mandrel It has a flange 71. at its inner end, and that the roll onhas a flange m at its outer end, and it will be further noticed that on the shaft 71 is the spring a between the outer bearing, 75, of the yoke and the roll m, which serves to hold the roll close to the bearing 7.1 except where, in the feeding of the metal, as hereinafter described, it is gradually forced forward against the compressive action of the spring. On this same shaft 1', between the spring a and the roll m, I also place the unscrewing-lever p, the purpose of which is to provide for the unscrewing of the pipethread protector from the mandrel h after it is formed. It will be noticed that, as shown by Fig. 8, this lever 1') has the curved arm 2, the inner face of which is concentric with the face of the mandrel h, but extends out to one side thereof, said inner face being serrated, so as to bind or hold upon the pipe-thread protector and hold it from turning when direction of the movement of the mandrel is reversed to unscrew it from the finished protector. This lever 19 thus mounted on the shaft '6 has also the handle p by which it is operated, said handle being grasped to hold the lever in contact with the protector to unscrew it. To hold this lever out of contact with the mandrel, I provide the rest 12 which extends out from the bearing k of the yoke in line with the shaft 1', so that the arm 12 on the lever may rest on the same and the inward movement of the serrated arm 1) against the mandrel be prevented.

In order to catch and hold the end of the metal strip in the winding operation, I provide a dog 1" pivoted to the yoke r on the shaft g back of the mandrel h and in line with the recess 7L2 in the flange 7r, the outer or free end of such dog extending over above the front face of the mandrel a short distance, so that it may take or bind into the edge of the strip to be coiled around the mandrel and hold the same. This dog is pressed into the strip by the face of the roll m. The several parts of the apparatus are of course intended to be made interchangeable, and to provide for the formation of different sizes of protectors, according to the different sizes of pipes, in making said changes the mandrels h and the rolls m may vary in diameter, the diameters of the pinions g and 1) being varied accordingly, so that practically the same surface-speed is maintained.

In the formation of the pipe-thread protectors according to the method and with the machine above described I provide close to the machine a suitable furnace for heating the blanks or metal strips from which the protectors are to be formed, and they are brought to a sufficient heat to render their inner faces sufiiciently soft to receive the impressions of the threaded mandrel h and to render the strips themselves sufficiently pliable to be pressed together in the coiling operation. Such a strip when properly heated is fed in between the threaded mandrel h and roll m and between the flanges h and m, which with the mandrel and roll form the pass, the mandrel being held up close to the roll by the foot-treadle Z The heated metal when held in the pass between the rolls is finally grasped by the dog 7, which in the rotation of the mandrel is brought between the mandrel and roll, so that its outer or free end is pressed into the metal strip, forming an indentation therein, as at e, and so holding to the strip and carrying and coiling it around the mandrel, while the strip is held close to the mandrel by the roll m, a sufficient force being exerted to impress into the inner face of the soft heated metal strip the threads on the mandrel h and so form thread-impressions thereon, which thread impressions are sufficiently deep to provide for the screwing of the threadprotector upon the pipe. As the strip is wound around the mandrel the first coil will overlap the inwardly-projecting end a, and as the strip is at a welding heat the end a will be welded to the coil. This will act to lock this end of the strip and prevent the displacement of the first coil due to any pulling strain. As the strip is wound around the mandrel and the thick part of the strip is brought between the flanges h and m, the roll m is forced along the shaft 41 against the pressure of the spring 11, so as to increase the width of the pass and to hold the metal strip against the flange h, and as the metal forms an additional coil the flange m presses the second coil against the first coil in such way as to make the coils lie close to each other, and in case there is any irregularity in the first coil to bind the second coilto fit the same, and in this way, while the strip is being held against the mandrel by the cylindrical face of the roll m and is held from turningthereon by the dog 4", the coils are forced close to each other between the flanges h and m, and the blank is thus rapidly and cheaply formed into th e pipe-thread protector having threads on the inner face.

As soon as the article is formed the operator removes his foot from the treadle Z which permits the free end of the shaft 2' to drop, carrying down with it the roll 'm, which is forced by the spring back to its normal position. At the same time it brings the unscrewing-lever 19 under the blank which has been formed upon the mandrel h. The operator then grasps the handle 19 and forces the serrated arm 19 of this lever into contact with the finished blank, and he reverses the direction of the movement of the shaft g, so that the mandrel will unscrew from the thread-protector, which has been formed thereon, and in such operation the lever 1) holds to the blank, moving with it and compressing the spring 71. until the blank is unscrewed from the mandrel and discharged from the machine.

The operation requires but a short time both to form the article and remove it from the mandrel, and the article can thus be formed very rapidly and at little cost over that of the metal employed, while for the purpose only the ordinary rolled metal strips are required, and it is only necessary to shear them diagonally, and if they are of small width this is not even necessary.

As the pipe-thread protectors are composed of two or more coils of metal which extend around the pipe at the same time, as above described, they have the peculiarity of holding to the pipe and will sufficiently protect the same from injury and hold to their natural form, and they have the peculiar action of screwing easily upon the pipe and being difficult to unscrew therefrom.

What I claim as my invention, and desire to secure by Letters Patent, is-

1. The combination with a threaded mandrel of a spring-actuated longitudinally-yielding roll adapted to hold the strip in contact therewith, and a holding device to engage with the strip, substantially as set forth.

2. The combination of a threaded mandrel having a flange at its inner end, a longitudinally-movable roll having a flange at its outer end, and a spring interposed between said roll and a suitable abutment, substantially as set forth.

3. The combination of a threaded mandrel having a flange at its inner end, a longitudinally-movable roll having a flange at its outer end, a shaft on which said roll is mounted, a spring encircling said shaft and interposed between said roll and an abutment, substantially as set forth.

4. The combination of a threaded mandrel having a flange at its inner end with a recess therein, a dog mounted on the mandrel-shaft and adapted to fit in said recess, a roll having its face in line with said flange and adapted to force the end of the dog into the blank, said roll having a flange at its outer end, and yielding connections providing for longitudinal movement between the mandrel and roll, substantially as set forth.

5. The combination of a threaded mandrel around which a blank is coiled, and an unscrewing-lever having a face adapted to hold the blank from turning when the mandrel is being rotated, substantially as set forth.

6. The combination of a threaded mandrel, a roll adapted to coil a blank thereon and an unscrewing-lever mounted on the roll-shaft and adapted to hold the blank from turning when the mandrel is being rotated, substantially as set forth.

7. The combination of a threaded mandrel, a roll adapted to coil a blank thereon, and an unscrewing-lever mounted on the roll-shaft and adapted to hold the blank from turning when the mandrel is being rotated, and a spring pressing against the lever, substantially as set forth.

8. The combination of a machine-frame f, having bearings f f the shaft 9 mounted therein and carrying the mandrel h, the bearing 1' pivoted on the machine-frame, the yoke 7s pivoted 011 the vertical shaft 1 and the shaft 71 mounted in the bearings 70' k of the yoke 7a and carrying the roll m, substantially as set forth.

9. A pipe-protector formed of a coiled metal strip having thread impressions 011 its inner face, said strip having one of its ends bent inwardly and overlapped by the coil, substantially as set forth.

In testimony whereof I, the said JOHN W. ABRAHAMS, have hereunto set my hand.

JOHN WVM. ABRAHAMS.

\Vitnesses:

ROBT. D. ToT'rEN, O. R. 00010;. 

